Abstract:

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Homogeneous BaTiO3 nano-sized powders were successfully prepared by spray pyrolysis
using multiphase plasma under the air atmosphere. Particle size, morphology, crystal phase
and crystallinity of as-prepared powders were characterized by SEM and XRD. The effect
of starting precursor solution on the formation of nanoparticles was investigated. The use
of Ba/Ti aqueous solution derived from malic acid led to formation of cubic BaTiO3
nanoparticles with 50 nm size.

Abstract: Mixed-conducting ceramic oxide SrFeCo0.5Oy powders were prepared by a citrate method, and
the contributing factors to the formation of homogeneous fine powder with a pure perovskite-type
structure were ascertained. The resulting powder is pure, homogeneous and possesses a reasonably fine
particle size. Attempts were made to understand the synthesis process and it was confirmed that the
method produces powder had greater composition uniformity, lower residual carbonate levels and smaller
particle sizes.

Abstract: The nano-sized Ba(Zr0.2Ti0.8)O3 powder was prepared by citrate sol-gel method. The crystal
structure and the particle size of the powder were characterized by XRD. The morphology of calcined
powder and the sintered ceramics was observed by TEM and SEM, respectively. The particle size of the
powders calcined at 600oC is about 10 nm. The dense ceramics can be obtained at sintering temperature of
1220 oC, which is much lower than that of the powder prepared by the conventional solid method. The
effects of Al2O3 additive on the sintering behavior, microstructure and dielectric properties of
Ba(Zr0.2Ti0.8)O3 ceramics were also investigated.

Abstract: Spherical LiNi0.5Mn1.5O4 powders were prepared by internal combustion type spray pyrolysis
apparatus using gas burner. The powder production capacity was 1 kg/h by this equipment. After
calcinations of as-prepared powders contained Ni at different temperatures from 800 to 1200 °C in
air for 10h, LiNi0.5Mn1.5O4 powders were obtained. As-prepared particles have a porous
microstructure with an average diameter of about 5 μm with narrow size distribution. XRD showed
that LiNi0.5Mn1.5O4 powders were well crystallized to a spinel structure with Fd3m space group.
LiNi0.5Mn1.5O4 powders calcined at 1000°C show good cycle performance with after 30 cycles
discharge capacity of 112mAh/g and 95% retention after 400 cycles between 3.5 V and 5 V.

Abstract: Nano-sized 8mol% MgO-PSZ powder was prepared via coprecipitation, Afterwards, the prepared powders were characterized by XRD and SEM technologies. The results clearly demonstrate that the calcined temperature can be feasible for the MgO-ZrO2 composite, crystal structure and particle size.

Abstract: The 0.95MgTiO3-0.05CaTiO3 (95MCT) powders and ceramics were prepared by a sol-gel method by using Mg(NO3)2•6H2O, Ca(NO3)2•4H2O and Ti(C4H9O)4 as the starting materials. The effects of calcination temperature on phase formation, morphology and particle size distribution of the proposed powders were examined, and the microwave dielectric properties of 95MCT ceramics made from different size particles were investigated. The dried gels were calcined at 600 °C, 700 °C, 800 °C and 900 °C, and the derived particle sizes of powders were 10-20 nm, 50-100 nm, 60-120 nm and 120-150 nm, respectively. The proper sizes, which range from 50-150 nm, lowered the sintering temperature of 95MCT ceramics effectively from 1400 °C to 1175 °C due to the high surface energy. Sintered at 1175 °C, the 95MCT ceramic prepared from 50-100 nm size particles had compact structure and exhibited good microwave dielectric properties: εr = 21.33 and Q×f = 36,315 GHz.